改自HeDaode 2007-12-28的代码
将之改为从硬盘读取后文件后,将MemoryStream放到内存中,提高后续查询速度
///<summary> /// 提供从纯真IP数据库搜索IP信息的方法； ///</summary> public class IPSearch { FileStream fileStream = null; static long[] ipArray = null; static long initPosition = 0; long ip; static MemoryStream ipFile =null; ///<summary> /// 构造函数 ///</summary> public IPSearch() { if (ipArray == null) { lock ("ip") { if (ipArray == null) { fileStream = new FileStream("f:/files/qqwry.dat", FileMode.Open, FileAccess.Read, FileShare.Read); ipArray = BlockToArray(ReadIPBlock()); initPosition = fileStream.Position; fileStream.Position = 0; byte[] bytes = new byte[fileStream.Length]; fileStream.Read(bytes, 0, bytes.Length); ipFile = new MemoryStream(bytes); fileStream.Close(); fileStream = null; bytes = null; } } } ipFile.Position = initPosition; Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);//使.net core支持gb2312编码 } /// <summary> /// 更新ip数据文件后,对内存中的流进行更新 /// </summary> public void ClearStream() { ipFile.Close(); ipFile = null; ipArray = null; initPosition = 0; } ///<summary> /// 获取指定IP所在地理位置 ///</summary> ///<param name="strIP">要查询的IP地址</param> ///<returns></returns> public string GetIPLocation(string strIP) { ip = IPToLong(strIP); long offset = SearchIP(ipArray, 0, ipArray.Length - 1) * 7 + 4; ipFile.Position += offset;//跳过起始IP ipFile.Position = ReadLongX(3) + 4;//跳过结束IP //IPLocation loc = new IPLocation(); int flag = ipFile.ReadByte();//读取标志 if (flag == 1)//表示国家和地区被转向 { ipFile.Position = ReadLongX(3); flag = ipFile.ReadByte();//再读标志 } //long countryOffset = ipFile.Position; string country = ReadString(flag); //if (flag == 2) //{ // ipFile.Position = countryOffset + 3; //} //flag = ipFile.ReadByte(); //loc.area = ReadString(flag); //ipFile.Close(); //ipFile = null; if (!country.Contains("市")) { return null; } if (!country.Contains("省")) { return country; } return country.Split("省")[1]; } ///<summary> /// 将字符串形式的IP转换位long ///</summary> ///<param name="strIP"></param> ///<returns></returns> public long IPToLong(string strIP) { byte[] ip_bytes = new byte[8]; string[] strArr = strIP.Split(new char[] { '.' }); for (int i = 0; i < 4; i++) { ip_bytes[i] = byte.Parse(strArr[3 - i]); } return BitConverter.ToInt64(ip_bytes, 0); } ///<summary> /// 将索引区字节块中的起始IP转换成Long数组 ///</summary> ///<param name="ipBlock"></param> long[] BlockToArray(byte[] ipBlock) { long[] ipArray = new long[ipBlock.Length / 7]; int ipIndex = 0; byte[] temp = new byte[8]; for (int i = 0; i < ipBlock.Length; i += 7) { Array.Copy(ipBlock, i, temp, 0, 4); ipArray[ipIndex] = BitConverter.ToInt64(temp, 0); ipIndex++; } return ipArray; } ///<summary> /// 从IP数组中搜索指定IP并返回其索引 ///</summary> ///<param name="ipArray">IP数组</param> ///<param name="start">指定搜索的起始位置</param> ///<param name="end">指定搜索的结束位置</param> ///<returns></returns> int SearchIP(long[] ipArray, int start, int end) { int middle = (start + end) / 2; if (middle == start) return middle; else if (ip < ipArray[middle]) return SearchIP(ipArray, start, middle); else return SearchIP(ipArray, middle, end); } ///<summary> /// 读取IP文件中索引区块 ///</summary> ///<returns></returns> byte[] ReadIPBlock() { long startPosition = StreamReadLongX(4); long endPosition = StreamReadLongX(4); long count = (endPosition - startPosition) / 7 + 1;//总记录数 fileStream.Position = startPosition; byte[] ipBlock = new byte[count * 7]; fileStream.Read(ipBlock, 0, ipBlock.Length); fileStream.Position = startPosition; return ipBlock; } ///<summary> /// 从IP文件中读取指定字节并转换位long ///</summary> ///<param name="bytesCount">需要转换的字节数，主意不要超过8字节</param> ///<returns></returns> long StreamReadLongX(int bytesCount) { byte[] _bytes = new byte[8]; fileStream.Read(_bytes, 0, bytesCount); return BitConverter.ToInt64(_bytes, 0); } ///<summary> /// 从IP文件中读取指定字节并转换位long ///</summary> ///<param name="bytesCount">需要转换的字节数，主意不要超过8字节</param> ///<returns></returns> long ReadLongX(int bytesCount) { byte[] _bytes = new byte[8]; ipFile.Read(_bytes, 0, bytesCount); return BitConverter.ToInt64(_bytes, 0); } ///<summary> /// 从IP文件中读取字符串 ///</summary> ///<param name="flag">转向标志</param> ///<returns></returns> string ReadString(int flag) { if (flag == 1 || flag == 2)//转向标志 ipFile.Position = ReadLongX(3); else ipFile.Position -= 1; List<byte> list = new List<byte>(); byte b = (byte)ipFile.ReadByte(); while (b > 0) { list.Add(b); b = (byte)ipFile.ReadByte(); } return Encoding.GetEncoding("gb2312").GetString(list.ToArray()); } }
测试:
[HttpPost("pt")] public IActionResult PayTest([FromQuery]string ip) { Stopwatch stopwatch = new Stopwatch(); stopwatch.Start(); IPSearch iPSearch = new IPSearch(); string result = iPSearch.GetIPLocation(ip); stopwatch.Stop(); return Ok(new { stopwatch.Elapsed,result}); }
第一次运行稍慢,以测试机的配置需要25~50毫秒之间
之后每次运行均在1毫秒以内
